Endpoint: significant paravalvular regurgitation (Grade II or greater)
Parameters:
(1) angle between the left aortic outflow tract to the ascending aorta, in degrees
(2) depth of the device in relation to the noncoronary cusp
The angle is between the axis of the first 4 cm of the ascending aorta and the axis for the left ventricular outflow tract (see Figure 1, page 1624).
The depth of the bioprosthesis is determined in the final aortogram following bioprosthesis deployment. It is the distance from the native aortic annular margin on the side of the noncoronary cusp to the most proximal edge on the corresponding side of the deployed stent frame (Figure 2, page 1625).
complex equation =
= (0.21314 * (angle)) - (1.8232 * (depth in mm)) + (0.091 * ((depth in mm)^2))
simple equation =
= (2 * (angle)) + (((depth of the device in mm) - 10)^2)
Paravalvular regurgitation was significant if:
(1) complex equation >= -4.0459
(2) simple equation >= 50
Performance:
• The complex equation had a sensitivity of 90% and specificity of 87%.
• The simple equation had a sensitivity of 85% and specificity of 87%.
